07 climate control issue.

[Passat my07]

Hi, I've found this forum very helpful in the past but now I've come across a problem that I can't find much info on so I thought I better register and ask.
It's an 07 2.0 fsi wagon and we have only owned it for a couple of months and climate control has been playing up. On long trips the air con works fine for about an hour and then all the dash vents close so the air can't get out. The compressor is still running and the air is cold but it can't get out of the box. I tried resetting the flap motors by holding the Econ button and the face vent button at the same time but it didn't really help. I also took it up to 29.5* and then back down to 17* and it worked again for a bit but then it closed up again.
Any ideas?
thanks.

[Passat my07]

I have noticed water on the passenger floor after stopping the car so I'm wondering if the evaporator is freezing up and not letting air through. It could be a tx valve fault. Any thoughts?

[2VWs]

It may be leaves and the junk around the evaporator and thus blocking the drain tube. It was the problem on a Commodore we had about a decade ago.

[Passat my07]

I replaced the pollen filter when I serviced it and it was fairly clean so I don't think anything would have reached the evaporator. Are faulty tx valves common on these cars?

[2VWs]

I replaced the pollen filter when I serviced it and it was fairly clean so I don't think anything would have reached the evaporator. Are faulty tx valves common on these cars?

You mentioned that water was on the floor. It is likely the drain tube is blocked. Have you checked it?

[Passat my07]

I only get water on the floor after I have been driving for a long time and the whole system won't blow any air through the vents. If I only drive for half an hour it just leaks onto the ground from the drain tube. I had a look under the bonnet when it was playing up after 500 km and the pipe was iced up all the way to the compressor.

[The One]

I only get water on the floor after I have been driving for a long time and the whole system won't blow any air through the vents. If I only drive for half an hour it just leaks onto the ground from the drain tube. I had a look under the bonnet when it was playing up after 500 km and the pipe was iced up all the way to the compressor.

Sounds like freezing up. Go on VAS/VAGCOM and check temps @ evap and see what they are..

[Passat my07]

If I purchase the cheapest rosstech cable will I be able to access everything I need? I don't have any sort of scanner for it at the moment.

[booba]

If I purchase the cheapest rosstech cable will I be able to access everything I need? I don't have any sort of scanner for it at the moment.

you should get microcan, that is probably the cheapest.

[The One]

If you know someone who has a scan tool that shows live data, perhaps ask if they can assist you?

[Passat my07]

Ok that all sounds like good info. Where is the cheapest place to buy the microcan from?
thanks.

[Passat my07]

I think you are on the money with the evap temps. I found a vw technical bulletin that says they updated the evaporator temp sender from jan 2007. It says the symptoms are low or no air flow. It looks like it was a warranty item if you complained but not a recall.
I pulled it out and had a look today and it's still got the original style sender. The updated one has a 45 degree bend and it's longer.
If anyone is looking for it on a right hand drive car you need to remove the lower console trim in the drivers footwell.
I think I'll still buy a microcan though because I'm sure I'll need it at some stage. Where should I get it from?
thanks.

[sn809]

Ross-Tech: Micro-CAN Interface

[Passat my07]

Thanks for that. So I should get it direct from the states and not from a local distributor?

[sn809]

That is the Micro-CAN you wanted to know about. First read up to check if it suits your car.
Although I was interested in getting one earlier, I am not so sure about it at the moment. The research I did led me to believe the best version is VCDS

https://www.google.com.au/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=vag+com+cable+volkswagen

I am sure others who have more info than me will be around to help you out soon.